Abstract:
GaN single crystals are used as substrates
for homo-epitaxial growth by MOCVD. Prior to growth, the N-face, or (000
1) plane, of the substrate crystals is polished to obtain off-angle orientations
of 0, 2, and 4- towards the [1 1 (2) over bar 0] direction. The hillock
density of the homo-epitaxial films grown on the misoriented substrates
is decreased as compared with the layers grown on the exact N-face. However,
in addition to the hillocks, triangular-shaped pits are formed on the films
grown on the misoriented substrates. The formation of the triangular-shaped
pits is described by the blocking of the anisotropic step-flow growth.